Audio signals typically comprise a combination of noise- and sinusoid-like signals. A distinction between sinusoids and noise is particularly relevant when processing speech signals, where the sinusoids define the “pitch” of the speaker, while the noisy components reflect the consonants in the speech signals. For these reasons, it is very interesting to be able to distinguish between these two signal categories in the context of a sound processor, and in particular in hearing devices, whose main goal is to enhance speech signals and intelligibility. Furthermore, many other applications can benefit from the ability to separately process sinusoids and noise, if a reliable means is provided to identify the presence of tonal signals, i.e. of sinusoidal components. Hence, there exists a need for improved means for reliably and easily detecting tonal signals.